Current dental implantations can be divided into a one-stage system and a two-stage system based on the designs of the dental implants and the corresponding surgery operations thereof. After a dental implant is implanted in an alveolus bone, a direct and rigid contact will be formed between the dental implant and the neo-bone during the osteo-concrescence process, and such a process is the so-called osseointegration, which provides well stability between the dental implant and the bone tissue. Generally speaking, it takes about six months for the alveolus bone of a supramaxillary to achieve the expected level of osseointegration, whereas it takes about three to four months for a submaxillary. In the one-stage dental implant system, a part of the dental implant is located at the outside of the gum, and an artificial crown will be mounted on the dental implant after the osseointegration. On the other hand, in the two-stage dental implant system, the whole dental implant is covered in the gum, and the gum will be incised for mounting the artificial crown after the osseointegration. Because the dental implant is covered in the gum during the osseointegration, the probability of infections and the external stimulus will be reduced, so that the dental implant can be integrated with the alveolus bone more stably.
The stability of the dental implant is a key factor in a successful dental implantation. The better the osseointegration is, the higher density the alveolus bone will have, and the higher stability the dental implant will have, such that the success rate of the regional dental implantation will be higher. Therefore, the stability assessment of the dental implant is a key step in the dental implantation. Presently, common measurements of the stability assessment of dental implants include X-ray image measurements and resonance frequency measurements. However, there is a big difficulty in quantity determination when doing the X-ray image measurements, where the bone variation less than 30% can not be detected thereby. Moreover, angles of taking X-ray images will affect the accuracy of readings; X-ray also harms human bodies, and the technicians of operating X-ray machines must be well-trained. Besides, X-ray imaging instruments are very expensive. Compared with X-ray image measurements, resonance frequency measurements do not have the mentioned limitations.
Currently, in the clinical practice, one of the resonance frequency measurements for assessing the stability of dental implants is the impulse response method, where a constant external impetus is provided to the dental implant using a hammer to directly impact the dental implant. A vibration response of the dental implant is received by a microphone and provided for frequency spectrum analysis, so as to obtain the resonant frequency of the dental implant and analyze the conditions of the implant/alveolus interface. The higher resonant frequency represents the better stability of the dental implant. Nevertheless, such an impulse response method only fits the one-stage system. Because in the two-stage system, the dental implant is covered in the gum and can not be impacted by the hammer to measure the stability thereof.
From the above description, it is necessary to provide a method to measure the resonant frequency of the dental implant without any contact, and such a method is suitable for both of the one-stage and two-stage dental implant systems. In addition, this non-contact method avoids the inconveniences of the conventional resonance frequency measurements, where a direct contact of external impacts is necessary. This non-contact method also decreases the psychological uncomfortableness of patients.
In order to overcome the drawbacks in the prior art, a non-contact apparatus and a non-contact method for stability assessment of dental implant are provided. The particular design in the present invention not only solves the problems described above, but also is easy to be implemented. Thus, the invention has the utility for the industry.